Fire consists of three essential elements. What is one of them?

One of the essential elements of fire is oxygen. For combustion to occur, a fire requires a chemical reaction that typically involves three components known as the fire triangle: heat, fuel, and oxygen. Oxygen is critical as it supports the chemical reactions that release energy in the form of heat and light during a fire.

Without a sufficient supply of oxygen, a fire cannot sustain itself. This is why firefighting techniques often focus on eliminating or reducing the oxygen available to a fire, such as using fire extinguishers or blankets to smother flames. The presence of oxygen in the environment allows for the burning of fuel, which is necessary for the generation of heat and the continuation of a fire.

While carbon dioxide can be produced as a byproduct of combustion and matches are tools used to initiate a fire, neither directly contributes to the establishment of a fire's fundamental requirements. Light is a result of the fire but does not play a role in its creation. Thus, oxygen is an indispensable component in the process of combustion and fire formation.